Indian Standard

ts t 4034 - 1979 ( Reaffirmed 2001 )

SPECIFICATION FOR CASTORS FOR HOSPITAL EQUIPMENT

( First Revision)
First Reprint NOVEMBER 1991

UDC 645.461:615:478

@ Copyight BUREAU OF INDIAN

1980 STANDARDS

MANAK BHAVAN, 9 BAHADLJRSHAH ZAFAR MARG
NEWDELHI

GrS

January

1980

is : 4034 - 1979

Indian Standard
SPECIFICATION FOR CASTORS FOR HOSPITAL EQUIPMENT

( First Revision )
Hospital
Chainan DR L. R. PATHAK McsRbWS Postgraduate Institute of Medical Education & Research, Chandigarh Nat Steel Equipment Pvt Ltd, Bombay SERI DARAYUS BHATRENA SHRI K. D. HATWRADX ( Alternate ) Ministry of Defence ( DGAFMS ) COL DALJITAM SIN~R Development Commissioner, Small Scale IndusSHRI K. M. DAR~AR tries ( Ministry of Industry ), New Delhi Directorate of Medical Education, Government of DR S. GNANADESIKAN Tamil Nadu of Industries, Government of JOINT DIRECTOR OF INDUSTRIES Directorate Maharashtra ( CSPO ) ASSTT DIRECTOR ox INDUSTRIES ( CSPO ) ( Alternate ) Tempo Industrial Corporation, Bombay SHRI V. S. KALBA~ SHRI ARVIND BOLAR ( Alternate ) Director of Industries? Government of Haryana SERI K. MANIVANNAN C EN T R A L Railway Board ( Minlstry of Railways) M~A~~~;AyO~~~o~~, Paoa C. BALA~RI~HNAN DIVISIONAL MEDICAL OFFICEI& BOMBAY ( Altcrnute ) Directorate of Industries & Commerce, GovernSHRI S. MUTEIAN ment of Tamil Nadu Directorate General of Technical Development, SHWI K. N. RAIKA~WAXY New Delhi Ministry of Defence ( R&D ) SFIRI V. K. SABBARWAL Ministry of Defence ( DGI ) GP-CAPT K. K. SAEAI SHRI K. K. GJXAI ( Al&mate ) Equipwell Corporation, Chandigarh SHRI BHUSBAN SAWZ~NEY SERI R. B. SETH International Industries, Bombay ( Continuedon haze 2 ) @ BUREAU OF Copyright 1980 lNDL4N Diregz;te

Equipment

Sectional

Committee,

CPDC 14

Represettling General of Health Services, New

STAMflARDS

This publication

is protected under the Zndian Copgrigfrt Act (XIV of 1957 ) and reproduction in whole or in part by any means except with written permission of the >ublirh~ shall be deemed to be an infrirwement of copyright under the said Act.

IS : 4034 - 1979
( Continuedfrom puge 1 ) Illembers Metal & Alloys Representing Industries, Tinsukia ( Assam ) Instruments )

S~rrtr I:AnULAL Tom SI~I~I R. N. Vra SII~I D. N. Vrc
SIIIII R. N. VIO ._

Government Institute of Surgical Technology, Sonepat ( Haryana Todi Industries Private Ltd, Bombay Ultradent Pvt Ltd, Bombay ( Alternafe ) All India Instrument Manufacturers Association, Bombay
( Alternale )

and

Dealers

Srrnr SUM 1'12~1~~s1r.4, Director ( Consr Prods & Med

SFI<I I'. _ K. Nasur.a

Instrs

Director )

General,

ISI ( Ex-@cio

Member )

Secretary Deputy SKRI D. K. AQRAWAL Director ( Consr Prods & Med Instrs ), IS1

Hospital
Members PROF J. S.. AXAND

Furniture

Subcommittee,

CPDC

14 : 1

SHIZI B. L. ARORA SXRI DA~AYIX B~ATHENA SIIRI K. D. HATJIIIGABI ( &tern&e ) Railwav Board I Ministrv of Railways ) OR J. K. CIIAUDIIUJ~Y ' Mini&y of Deft&e ( DdAFMS ) ' ' COL Dar.arrranf Sracir Directorate General of Health Services ( Ministry Sun1 P. C. KAPUR of Health & Family Welfare ), New Delhi Directorate General of Supplies & Disposals, New SHRI S. C. KAPUR Delhi of Industries & Commerce, GovernMANAGER ( INDLWTRIBL ENCU- Department ment of Tamil Nadu NEERINQ ) Office of the Development. Commissioner, Small SHRI L. .M. MATEUIZ ptDE;hd;ustries ( Mmistry of Industry ), e Janak Manufacturing Works, Bombay Saxr A. J. MEHTA New Haven Steel Ball Corporation Pvt Ltd. SARI P. C. SALQAON~AR Bombay Dire&orate General of Health Services, New DR R. S. SAHENA Delhi Paul Engineers, New Delhi SHRI V. N. SEEHEI SHRI S. P. SEKERI (Alternate ) Special Equipment Co, Bombay SHRI E. A. SIIAIKH SERI A. J. SHAIKB ( Alternate) Spencer & Co, Madras SHRI R. DE SOIJZA The South India Surgical Co, Madras SHRI T. P. VENU~OPAL
SIiRI R. N. Vxa SHRI P. K. NARTJLA S~IRI S. K. NARULA ( Alfernate Imperial Surgical Co Pvt Ltd, Bombay Narula Udyog ( India) Pvt Ltd, New Delhi

Postgraduate Institute of Medical Education Research, Chandigarh India Medico Instruments, Delhi Nat Steel Equipment ( Pvt ) Ltd, Bombay

&

)

2

IS:4034

-1979

Indian Standard
SPECIFICATION FOR CASTORS FOR HOSPITAL EQUIPMENT

( First Revision)
0. FOREWORD

0.1 This Indian Standard ( First Revision ) was adopted by the Indian Standards Institution on 30 April 1979, after the draft finalized by t~he Hospital Equipment Sectional Committee had been approved by the Consumer Producti Division Council. 0.2 The formulation of Indian Standards on hospital equipment has been taken up at the instance of the Advisory Committee for Development of Surgical Instruments Equipment and Appliances, Government of India. 0.3 This revised standard has been prepared in the light of the comments received from the industry and the Controllerate of Inspection General Stores (GIGS ). The main change is in the dimension of the axle which has now been related with the outside face of the nut. 0.4 The castors specified in this standard are for use on hospital equip ment. They may also be used on any other equipment for which they are found suitable. 0.5 In addition to' rubber treads, the castor wheels in rubber, nylon or polymer may also be used. 0.6 Only essential dimensions have been specified to ensure interchangeability and to keep the spares to the minimum. Thegeneral design details and other features have been left to the manufacturers so as not to restrict the development of new designs. 0.7 The castors may be made fixed-type also, if required by the purchaser. Other special features for specific use, for example, non-clogging type, locking, etc, may be provided at the option of the purchaser. . 0.8 In preparing this standard, considerable assistance has been derived ftom the following: IND/GS/MED 264 (C) Castor, for assorted aseptic furniture. Chief Inspectorate of General Stores, Ministry of Defence, Government of India.

3

1s s 4034

l

1979 lekki. Polski Komitet Polish castors, light type.

PN/Z/78045-1957 Kolka orumione-type Normalizacyjny ( Hospital furniture, Standards Committee ). BS 20150 : 1961 Electrical resistance products made -from flexible Standards Institution,

of conductive and anti-static polymeric material. British British Com-

BS 2099 : Part I : 1970 Castors for hospital equipment. Standards Institution. CS 223-59 Castors, wheels and glides for hospital equipment, mercial Standard, USA.

0.9 For the purpose of deciding whether a particular requirement of this standard is complied with, the final value, observed or calculated, expressing the result of a test or analysis, shall be rounded off in accordance with IS : 2-1960*. The number of significant places retained in the rounded off value should be the same as that of the specified value in this standard. 1. SCOPE 1.1 This standard lays down requirements on hospital equipment. 2. TERMINOLOGY 2.0 For the purpose of this standard, shall apply ( see Fig. 1 ). 2.1 Castor between the a geometrical otherwise. top plate or the following terms and definitions for swivel type castors for use

- An assembly including a wheel fitted by means of an axle two flanges of an offset fork which can swivel freely around vertical axis, with or without bushings or bearings, plain or The swivel axle is fitted on a mounting part which can be a a stem.

2.2 Overall Height or Effective Height - The vertical distance between the bottom of the castor wheel and the surface on which the equipment normally rests, which is also equal to the vertical distance of the floor surface and the equipment. 2.3 Fork - A part with two flanges between which revolves the wheel. means 2.4 King Pin -A swivel bearings parts.
*Rules for rounding

through

which

goes the axle and the alignment of

for effectively

maintaining

off numerical

values ( revised

).

4

SWIVEL

RADIUS

FIG. 1 .NGMENCLATURE FO'R CASTORS 5

IS I 4034 - 1979 2.5 Maximum Load Capacity - The load each castor can be expected to carry when moved on a smooth floor at speeds not exceeding 3.0 km/h.
NOTE - Uneven 60 percent. floors may derate the given load ratings to approqimately

2.6 Offset ( or Lead ) - The horizontal distance between the centre line of the swivel bearing and the axle of a castor as mounted for normal use. 2.7 Size Nominal diameter of the wheel. of the castor assembly that extends upwards

/

2.8 Stem - The portion into the equipment.

2.9 Swivel Radius - Horizontal distance between the centre line of swivel bearing and the most distance point on the wheel tread. It is also considered to be the radial clearance that permits the castor to swivel 360" without obstruction. 2.10 Test Load - The load each castor is required to carry when complying with each test procedure. 2.11 Top Plate - A horizontal plate which provides for attaching to the equipment by means of bolts. castor

2.12 Tread Width - The width of tread or tyre is the linear distance measured across the base of the tread ( not face ). 3. MATERIAL 3.1 Castor 7 Rubber shall be used for the manufacture of castor wheels. Other suitable materials may also be used if they meet the requirements of this sthndard. 3.1.1 In case of anti-static castors, the rubber and other materials used for the wheels shall meet the requirements of anti-static properties as specified in 9.1 and 9.1.1. 3.2 Top Plate, Fork, Plug ( or Stem ) - These shall be of mild steel or suitable aluminium alloy and of such thickness and form that these will provide sufficient strength and rigidity to meet the requirements as specified in the standard. 3.3 The material for axle, nut and other parts shall be mild steel. 4. IDENTIFICATION 4.1 The standard type references shall be derived as follows: Hospital Castor H; Normal Duty N; Light Duty L Nominal Wheel Sizes : 50 x 20 x 6; 65 x 25 x 6; ctc 6

IS : 4034 - 1979 Solid Fitting : Expansile Plu, rr Xl%; Screwed Plug SK; Plate Pl Wheel tyrc Tube bore Finish E.van$le: A castor of rubber wheel, normal duty, wheel size 50 ~20 X 6, solid plug fitting shall be designated as HN 50 x 20 X 6 PC, wheel tyrc, tube bore, finish 5. DIMENSIONS 5.1 The main dimensions of the castors shall be as given in Table 1. 1 } Description i Plug PCr; Spring Core SC;

given by the manufacturer

5.1.1 Light Duty Castors - These shall conform to the dimensions given in Table 1 except that the maximum load capacity per castor shall be 25 percent of the loads shown, subject to a minimum of 6 kg. 6. CONSTRUCTION 6.1 Wheels - Wheels shall have (a) a soft-rubber tread securely vulcanized to a hard-rubber core or tread base, or (b) hard rubber or other suitable composition and be integrally moulded. The tread and core shall have compressive, flexural and impact strength adequate for the purpose intended and shall be resistant to the destructive action of water, mild acids and ordinary cleansing compounds. 6.2 Fork - The fork shall be well-formed will provide suflicient strength and rigidity. and of such thickness that it

6.3 Axle - The axle design and assembly shall be such that the axle will not revoive and the nut wiii not become loosened under normal working The method of assembly shall also prevent the clamping of conditions. the wheel between the.flanges of fork when the nut on the axle bolt is drawn uptight. The end of the axle shall not prqject beyond the outside face of the nut or any other fixture for more than 6 mm and shall have a domed finish. 6.4 Bearings 6.4.1 IVheel BearitzgJ -When the wheels are provided with bush or ball bearing, the races shall be fully case hardened. For ball bearings, the races shall provide curvilinear contact with the balls and the inner races shall butt at a central point so as to provide the equivalent means of avoiding preloading and binding of the bearing members when the axle nut is drawn up tight. The inner races shall not revolve with the wheel,

7

IS : 4034 - 1979 6.4.2 Swivel Bearings - Castor swivel shall have ball bearings. In swivelling under load, all forces ( direct, component thrusts ) shall be effectively transmitted through the ball bearings in contact with the respective raceways. The races in swivel bearings shall provide curvilinear contact with balls. The races shall be fully case-hardened and these shall be either ground smooth or die-formed and coined. 6.4.3 Balls - The balls of wheel and swivel bearings to 700 to 800 HV and shall be ground and polished. shall be hardened

6.5 King Pin in Swivel Bearings - The king pin where used shall be of steel and be secured in place so that in swivelling, it shall not be in i'rictional contact with any member of the swivel bearing assembly. The Kng pin shall be of such a design, construction and material that it will rnaintain effectively the proper relative position of swivel bearing components for the life of the castor under normal working conditions, 6.6 The fit of the components to each other shall be such as to obviate wobble or rattle. Under no load the castor shall roll freely and the fork of swivel castors shall swivel freely. 6.7 There parts. shall be adequate provision for the lubrication of the moving

1, METHODS

OF ATTACHMENT

7-1 The methods of attachment of the castors to the equipment shall be one of the following and shall be identified by the letter code shown against each attachment: Attachment Expansile Spring Screwed plug fitting ( metal or rubber )
Code

Solid plug fitting core fitting plug fitting of Fittings

XPG PG SG SPG PT

Plate fitting ".`,? Detailed Requirements

of expansile plug shall be as 7,2.1 Expansile Plug ( XPG ) - Diameter ;:;&ficd according to internal diameter of tube, it is intended to fit and si,zlI be capable of being tightened by hand or tool to resist a withdrawal ~111 of 20 kg for a period of one minute. of the solid plug shall be as 7.2.2 Solid Plugjtting ( PC) - Diameter cpecified accarding to internal diameter of tube it is intended to fit, The

8

IS : 4034 - 1979 -.-_^_---TABLE (Chrszs

1 DIMENSIONS

FOR

CASTORS

5.1, 7.2.5, A-2.1, A-3.1, A-4.1 ndB-2.1.2) All dimensions in millimetrcs

MaxInrunf Lam CAPAClTY PER
CAST011 k

OVERALLOR EFEECTIVE HIXGIXT

OFFSET

PLUG(OR STEM) LENGTH

(4
(4) 65 & 1.5 85 f 2 loo* 2 125 f 3 150 f 3 175i5 200&t 255 f 5

(a)
(5) 15 f 3 25&- 4 35 f 5, 40`*5 45 f 5 50 * 6 60 f 6 70 f 7

(1)
HN 50 HN 65 HN 80 HN 100 HN 125 HN 150 HN 175 HN 225 *For screwed plug

(2) 50 x 20 65x25x 80 x 25 100 x 30 125 x 30 6 6 % 6 x 8 x 12 x

(3) 18 22 34 54 54 54 54 68

C6j
25 (20). 35 (20)* 35 50 50 60 60 70

150 x 40 x 12 175 x 40 x 12 225 x 50 x 15 fitting.

9

As in the Original Standard, this Page is Intentionally Left Blank

plug shall be retained by a grease nipple or set screw of 5 mm 1113 to and including 65 mm nomina! diameter castors and 6 mm for 80 Jnrn nominal An additional set screw shall bc fitted to diameter castors and above. ` fixed ' and brake castors. 7.2.3 Spring Core Fi/titrg ( SC) - This shall consist of a stem having n suitable flange at its lower end to carry the load and a steel spring rctaiJ1c.r shaped to fit tightly into the attachment when forced in. The core when properly applied shall withstand an extractive force of 4 kg for one minute. This shall be checked after the core has been inserted and pulled out 10 times. 7.2.4 Screwed PlugFitting ( SPG) - This shall consist of a threaded stem The stem shall be at least of tlte and a nut securely fixed to the stem. length specified in Table 2 with threads up to 20 mm. This is rccommended to be used up to 65 mm normal duty castors only and up to 100 nlm light duty castors. 7.2.5 Plate Fitting ( PT) - Fixing centres and hole sizes shall bc as given in Table 2 ( for Fig. .see Table 1 ).
TABLE 2 FIXING CENTRE AND HULE SIZES

( Clauses 7.2.4 and 7.2.5 )

IDENTIFICATJON

All dimensions DIA OF WIIEEL SJZlZ

in millimetres.

d, x bl x d,

HOLE* (ds)
(3) s 6 8 8 10 10 10 16

FIXINQ CENTRJW Cl x 82
(4) 60 x 40 60 x 40 80 x 60 80 x 60 105 x 75 105 x 75 105 x 75 150 x 135

MOUNTING PLATE ~~~~~~A__~~~~ 19 11
Nominal (5) 80 f 80 f 105 * 105 f 135f3 135 f 135 f 190 f

KOm-iRal

(1)
HN HN HN HN HN HN HN HN 50 65 80 100 125 150 175 225 50 x 65. x 80 x 100 x 125 x 150 x 175 x 225 x

(2)
20 25 25 30 30 40 40 50 x x x x x x x x 6 6 6 8 12 12 12 15

(6)
2 2 3 3 3 3 3 60 + 2 60 IfI 2 85 & 2 85 f 2 105 &3 105 * 3 105 f 3 170 f 3

*With a tolerance of i 0.5.

8. FINISH 8.1 All mild steel parts shall be painted to shades white, off white or sea green as required by the purchaser. However, prior to painting these shall be degreased, rust-proofed by phosphating and then suitably protected by an anti-corrosive primer, either by brushing or by spraying and then In finished in stove enamel or air drying enamel of the specified shade.

IS:4034-

1979

may' be.

evrrv instance each coat shall be scnamtelv stovcd or air tlrictl as the case `I'hc resulting finish in citi& c&e shall be linrcl and sltnll not rcdily chipor Ilalic. Alternatively the mild sterl l):lrts shall lx c~llrortGllm l~l;Ilcxl ov(`r IIickcl or c;lclmium l>latcil or zinc: l)l;ltc*tl. `l'hc cllIYjllIillIll <~Il~l I\iC!iC'lplating sllall be according to Service ( :ratlc No. 3 of IS : IU~Gl'Vi::`~. 9. PE&QRMANCE
- The assemblecl castors shall be tested for thrir durability it accordance with Appendix A. These shall meet a11 the rrquircmcnts of th test and still be capable of useful srrvice. Anti-static castors shall meet i n addition, the requircmcnts of Appcnclis 1%. 9.1 Durability

shall be carried out separately as the severity of the lnttrr trst may produce temporary conditions in the tyrc material which could give mislcaclinji results in the former test. The limits of resistnncc of anti-static castors shall bc as stntcd in Appendix B. 10. MARKING shall bc clearly and indelibly marked with the mnnuinitials or recognized trade-mark. 10.1.1 Anti-stdic Crtsto~s - When castors are required to be anti-static they shall be tionspicuously and indelibly marked to indicate that they are anti-static. The marking shall be as follows: facturer's name, a) The exposed part of the wheel centres shall be durably finished in yellow similar to No. 355 Lemon as shown in IS : 5-l96l.t. b) The tyres shall be marked with 6n indelible indication not less than 16.0 mms in area in yellow similar to No. 355 Lemon as sho.wn in IS : 5-1961-f and not less than 6 mm wide the words ` ANTI-STATIC ' where practicable incorporated thereon. 10.1.2 The castors may also be marked with the IS1 Certification Mark.
NOTE -The use of the IS1 Certification Mark is governed by the provisions of Marks) Act and the Rules and the Indian Standards Institution (Certification Regulations made thereunder. The IS1 Mark on products covered by an Indian Standard conveys the assurance that they have been produced to comply with the requirements of that standard under a well-defined system of inspestion. testing and quality cor$trol which is dcviscd and supervised by ISI and operated by the producer. IS1 marked products are also continuously checked by IS1 for conformity to that Details of conditions under which a licence for the standard as a further safeguard. use of the ISI Certification Mark may be granted to manufacturers or processors, may be obtained from the Indian Standards Institution.
*Specification (jirs1 revision ). tSpecification for clcctroplatcd for colours coatings mixed of nickel paints and chromium on iron and steel

9.1.1 `k test for anti-static Cntures from and before the test for durability,

10.1 The castors

for ready

( second rerision ).

12

1s : 4034 - 1979 11. PACKING 11.1 The castors shall be packed according

to their sizes. Each box shall carry a label indicating the identification of the castors ( see4.1 ) with the manufacturer's name, initial or trade-mark. In addition, label shall carry the word ` ANTI-STATIC ' in case of anti-static tyres.

APPENDIX A ( Clause 9.1 yb
TEST FOR PERFORMANCE A-l. TEST CONDITIONS A-l.1 Each castor submitted
as detailed for test shall perform all the test programmc in A-2 to A-5 consecutively and in that order.

A-l.2 For each part of the test, the castor shall be mounted in its norrnnl vertical operating position on a clean, smooth, lcvcl and rigid su~.lY~cc, and the relevant test load shall be applied continuously at thr point \~lurc: the castor should normally accept the wright of the cciuiprncrrt it is tlcsi~ncd to carry. All tests shall be conductccl at room teinpcraturc and ruuriillg tests shall be conducted at speeds not exccccling 3.0 knljh. 0th~ test conditions~shall be graduated according to wl~ecl cli;tmct~cr x clctailccl in Table 3. Light duty castors shall bc subjcctrd to similar tests and conditions, at 25 percent of the stated loads, with a minimum set at 6 kg.
TABLE 3 TEST ( Clauses9.1, A-l .2, A-2.1,
SL TEST DATA

DATA FOR HOSPITAL CASTORS A-3.1, A-4.1, A-4.1.1, A-G.1, A-G.3 unrl A-G.4 )
NOMINAL DIAMETEII OB \VIIW:L, mm

No.

r-----HN 50

HN 65 (4) 66 22 19 1:o 0.5 2.0 0.5 0.75 10

--_--h-_--._--_----~ HN HN HN 80 100 125 (5) 102 34 22 1.0 0.75 2.25 0.5 0.75 10 (6) lG2 54 38 1.0 1.0 3.0 1.0 1'0 10 (7) 162 5.1. 38 1.0 1.0 4..0 1.0 1.`" ._I 16

1-1X 150 (!i) Ih:! 5.1. 38 1.0 1% 4.0 1.0 1.4 16

1IN 173 (!J)

IIN 225 (1U) 20 1. (18 50 1.0 1.0 4.0 1a0 "..; 16

(3)
i) ii) iii) iv) v) Vi) Vii) viii) ix) Static test Smooth running test Hazards running test Time ( hours ) Static test Smooth running Hazards running test Wheel rock, mm Swirl rock, ni*n ~1,ti;tlrdJ Height of drop, mm 54 18 11 1.0 0.5 1.5 0.5 U.75 10

' 162
5 -1. 30 I.0 1.U 4..0 1'0 1.;; 16

13

A-2. STATE

TEST
on the surface plate and a test load The actual static test load for each (the test load is equal to 3 times the Table 1).

A-2.1 The castor shall be mounted applied for one hour continuously. size of castor is given in Table 3 maximum load capacity as given in A-3. SMOOTH RUNNING TEST

A-3.1 The castor shall be mounted
applied. (the test in Table given for

on the surface plate The test load for each size of castor shall be as load is exactly equal to the maximum load 1 ). The loaded castor shall be run for a total the relevant wheel diameter in Table 3.

kind the test load given in Table 3 capacity as given period of time as

A.4. HAZARDS RUNNING TEST A-4.1 The castor shall be mounted
on the surface plate and the test load applied. The test load for each size of castor shall be as given in Table 3, .~ntl ~ll;111bc not less than GO percent of the maximum load capacity as givcil in ?`nble 1. The lo~lecl castor shall be run for a total period of time ;IJ $\cn for the relevant wheel diameter in Table 3. A-4.1.1 ~lilr~l~/fs - During the hazards running test, the castor shall i,~`:-.r;ii':f,.' <I , at least once in c\:ery 3 m of travel, a hazard, as shown in Fig. 2 ~;.i~`il:I vertical drop to tile dimensions as given for the relevant wheel tlian:eter in Tabie 3.

FIG. 2

HAZARD

IS : 4034 - 1979 A-6, TEST REQUIRE-MENTS A-6.1 The quality of the assembled castors shall be such that if tcstetl in accordance with -4-l to A-5, at the appropriate loads and for the periods stated in Table 3, they shall be still capable of useful service. Their abilit) to meet this requirement shall be assessed by a close examination of tcstctl castors for the following indications of breakdown, A-6.2 Tyres - The quality of the tyres shall be such that they shall sholv no substantial flattening of the wheel if subjected to the static load test ( A-2 ). Any deformation that may exist after this test shall entirely disappear after running the castor for 10 minutes in similar conditions to those for the smooth running test ( A-3 ). A-6.2.1 On the completion of the tests as detailed in A-2 to A-5 the tyres shall show uniform and regular wear, without cracks, flats 01 grooves. A-6.3 Wheels - The wheel centre and the spindle shall be free from cracks; any wear in the bearing at the end of the test programme shall be such that the total amount of rock on the axle, measured on the periphery of the tyre shall not exceed the limits as given in Table 3. A-6.3.1 The measurement by letter ` A ' in Fig. 3. of wheel rock shall be made as indicated

--hiFro. 3
WHEEL ROCK

A-6.4 Swivels - Any wear in the swivel bearing at the end of the test programme shall be such that the total amount of movement at the centre of the wheel axle shall not exceed the limits given in Table 3. The measurement of swivel rock shall be made as indicated by letter ` Z ' in Fig. 4, and shall be taken when the castor mounting is rightly held.

15

is:4034

-1979

`L
FIG. 4

PLATE STEM

OR

SWIVEL

ROCK

A-7. ADJUSTMENT A-7.1 Castors which are so designed as to allow for ad_justment to take up any wheel or swivel rock shall not be so adjusted after the test before examination.

APPENDIX B ( Clauses 9.1 and 9.1.1)
METHOD OF TESTING ELECTRICAL RESISTANCE OF CASTORS B-l. METHOD

B-l.1 The tyre should be cleaned by rubbing with a dry fullers earth using clean pad of cotton wool, care being taken to avoid straining the tyre materials. B-1.1.X After all traces of the powder have been cleared away, the surface shall be wiped over with a pad moistened with distilled water, and rubbed dry with a clean cloth. B-2. TESTING PROCEDURE should not be capable of dissipating a potential more than 2 difference

B-Z.1 The test circuit into the test sample.

W

B-2.1.1 The applied voltage shall maintain least 40 V across a test load of 10 000 ohms.

of at

16

B-2.1.2 The tyres shall be kept in contact with an insulated wet metal piate by means of a pressure between 5 and 10 percent of the rated load appropriate to the castor ( see Table 1). The test voltage shall be a@plied between the insulated plate and the appliance contact points on the castor and the resistance through the castor determined by measuring either the current or the voltage across it by either of the test circuits shown in Fig. 5.

5A

Meter reading between 5 and 10 mA indicates sample resistance less than 10 000 51

56

Meter 10000 s/V Meter reading below 50 V indicates sample resistance less than 10 000 Sk

Fm. 5 B-3.

TESTCIRCUITS

TEST RESULTS

points around the circumference of the wheel and the results for new castors shall always be less than 10 000 ohms, any castor failing to meet this requirement shall be rejected.
NOTE 1 -Most insulation testers are unsuitable for testing castors having upper resistance limit of 10 000 ohms because of the very small deflection of the pointer at low resistance values.

B-3.1 Tests shall be made on at least five different

resistance meters NOTE 2 - Most multi-range are liable to give inconsistent measurements.

employ

very low test voltages

and

17

BUREAU
Headquarters:
Manak Bhavan,

OF

INDIAN

STANDARDS

9 Bahadur

Shah Zafar Marg, NEW DELHI 110002

Telephones: 331 01 31, 331 13 75
Regional Central *Eastern Offices:

Telegrams: Manaksanstha ( Common to all Offices) Teelephone
I 331 01 31 331 13 75

: Manak Bhavan, 9 Bahadur Shah Zafar Marg,
NEW DELHI 110002 : 1 /14 C. I. T. Scheme VII M, V. I. P. Road,

36 24 99 18 43 16 41 24 42 25 19 2916 92 95

Northern

2 I 3 41 Southern i C. I. T. Campus, MADRAS 600113 41 r 41 tWestern : Manakalaya, E9 MIDC, Marol, Andheri ( East ), 6 32 BOMBAY 400093

Maniktola. CALCUTTA 700054 : SC0 445-446, Sector 35-C, CHANDIGARH 160036

Branch Offices: Pushpak'. Nurmohamed Shaikh Marg, Khanpur, 2 63 48 AHMADABAD 380001 I 2 63 49 SPeenya Industrial Area 1st Stage, Bangalore Tumkur Road 38 49 55 BANGALORE 560058 38 49 56 I Ganaotri Comolex, 5th Floor. Bhadbhada Road, T. T. Nagar, 667 16 -~ BHOPAL 462003 5 36 27 Plot No. 82183. Lewis Road. BHUBANESHWAR 751002 3 31 77 5315, Ward No. 29, R.G. Barua Road, 5th Byelane, GUWAHATI 781003 23 1083 5-8-56C L. N. Gupta Marg ( Nampally Station Road ), HYiJERABAD 500001 6 34 71 R14 Yudhister Marg, C Scheme, JAIPUR 302005 I 6 98 32 21 68 76 117/418 B Sarvodaya Nagar, KANPUR 208005 { 21 82 92 Patliputra Industrial Estate, PATNA 800013 6 23 05 /6 21 04 T.C. No. 14/l 421. University P.O.. Palayam 16 21 17 TRIVANDRUM 695035
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/nspection Offices ( With Sale Point ): Pushpanjali, First Floor, 205-A West High Court Road, Shankar Nagar Square, NAGPUR 440010 Institution of Engineers ( India ) Building, 1332 Shivaji Nagar, PUNE 411005

2 51 71 5 24 35

*Sales Office in Calcutta ir at 5 Chowringhoe Approach, P. 0. Princep 27 68 00 strwt. Calcutta 700072 tSaler Office in Bombay is at Novrlty Chambers, Grant Road, 89 65 28 Bombay 4O@M7 iSales Office in Bangalore ir al IJnity'Building, Narasimharaja Square, 22 36 71 Bar&ore 560002 Reprography Unit, BIS, New Delhi, India